Previously known autofeed screwdrivers suffer the disadvantage that they must be adjusted or modified so as to be able to drive screws of considerably varying lengths. Previously known autofeed screwdrivers utilize a number of different mechanisms to hold the screw and/or strap of a screwstrip so as to locate a screw to be driven and supporting the spent strap on a forward surface of an exitway. However, previously known devices suffer the disadvantage that they do not utilize a combination of these features in a tool adapted to drive screws of different lengths.
Previously known devices suffer the disadvantage that the spent strap exiting from the tool is only engaged on a forwardly directed surface of the spent strap.
Another disadvantage with previously known devices is that some screwstrips have their straps located at different distances from their heads than other screwstrips. The relative position of the strap on the screw typically has been greater for screws such as 3 inch and 3½ inch lengths than with shorter screws. This arises since it is advantageous to have a strap for longer screws closer to a mid-point along the length of the screws to assist in stabilizing the screws held in the strap, however, this presents difficulties in adapting a tool to drive screwstrips with straps at different distances from the heads of the screws.
Another disadvantage with previously known devices is that they do not permit holding the screwstrip both by engagement of the next screw to be driven and support of the spent strip on a forward surface in the exitway.
Another disadvantage is that known devices do not provide a useful mechanism for driving screwstrips carrying indexing mechanisms on the strap.